Successful Reintroduction Research Articles

Tigers bringing risk and security: Gendered perceptions of tiger reintroduction in Rajasthan, India.

Human-wildlife conflict has been documented to impact some communities heterogeneously, particularly along gender lines (e.g., women experiencing inequitably increased workloads and economic hardship, and decreased physical safety and psychological wellbeing), leading to different attitudes towards wildlife. Despite possible gendered discrepancies, women's perceptions of conservation management are often insufficiently explored, leading to incomplete understandings of conservation dynamics, and unjust conservation policies. In an effort to investigate if and how perceptions of tiger reintroductions are disparate, we conducted focus group discussions with women and men living in and around Sariska Tiger Reserve in Rajasthan, India. Results demonstrate clear gendered delineations in perceptions, where male participants predominantly focused on economic and ecological benefits, and female participants highlighted threats to personal safety and hidden costs (e.g., potential abuse, dowry concerns). This research underscores the importance of documenting and understanding gendered perceptions of carnivores to achieve the broad community support necessary for successful reintroduction efforts worldwide.

Offspring of translocated individuals drive the successful reintroduction of Columbian Sharp-tailed Grouse in Nevada, USA

Abstract Translocations of North American prairie-grouse (genus Tympanuchus) present a conservation paradox wherein they are performed to augment, restore, or reintroduce populations, but translocated individuals exhibit a diminished ability to contribute to population restoration. For reintroduced populations without immigration, persistence can only be achieved through reproductive contributions by translocated individuals and their progeny. Due to the disruptive nature of translocation (e.g., physiological chronic stress), progeny produced at restoration sites may outperform founder populations in terms of demographics, but this hypothesis has yet to be tested. We reintroduced Columbian Sharp-tailed Grouse (T. phasianellus columbianus; CSTG) to north central Nevada from 2013 to 2017 and used integrated population models (IPMs) to evaluate the process of population establishment and estimate latent contributions of progeny hatched at the restoration site to population rate of change (λ^). Specifically, we used annual lek (i.e. communal breeding arenas) counts and demographic data from translocated individuals to build two separate IPMs to estimate λ^. While keeping demographic contributions by translocated individuals identical between models, one IPM assumed local progeny performance was demographically similar to translocated individuals (i.e. the baseline-IPM), and the second assumed that local progeny performed demographically similar to non-translocated CSTG (i.e. the informative-IPM). The baseline-IPM predicted strong population declines following the conclusion of translocations and extirpation by 2020, and it failed to predict observed lek counts. Conversely, the informative-IPM predicted population growth rates (λ^ = 1.17, 95% credible interval [CI]: 0.74–1.50) that were more similar to field observations. Offspring of translocated individuals likely perform at similar levels to non-translocated populations, and by not accounting for demographic differences between translocated individuals and non-translocated progeny hatched at the restoration site, managers could underestimate population performance and persistence. Thus, translocation practices that maximize the number of offspring immediately recruited into restoration sites are likely to be the most successful.

Clozapine-induced myocarditis and patient outcomes after drug rechallenge following myocarditis: A systematic case review

Clozapine is underutilized due, in part, to concerns about rare but severe adverse drug reactions, including cardiac inflammation and injury (myocarditis). Risk factors for clozapine-induced myocarditis are limited and predictors for the successful rechallenge of clozapine after an episode of myocarditis are even more poorly understood. We conducted a systematic review, in accordance with the PRISMA recommendation, of published case reports to describe demographic and clinical characteristics of patients with clozapine-induced myocarditis and identify potential markers of clozapine rechallenge success. A total of 180 cases from 88 articles were evaluated. Male cases of clozapine-associated myocarditis were more frequently reported than female cases by a ratio of 6:1. Less than half of patients reported the presence of chest pain (35%) or flu-like symptoms (43%) but increases in troponin or C-reactive protein were present in 87% of cases. Clozapine rechallenge was carried out in 34 (2 female) cases, with successful reintroduction in 22 (2 female) cases (64.7%) and one fatality (2.9%). No demographic or clinical markers were significantly associated with rechallenge success after correction for multiple testing. Standardized reporting of clozapine-induced myocarditis cases is needed to facilitate the identification of factors associated with successful rechallenge.

Factors influencing reintroduction of peanut and tree nuts after negative oral food challenges in children

BackgroundCompliance with reintroduction of foods after a negative oral food challenge (OFC) is variable. Ongoing avoidance of tolerated foods is associated with recurrence of allergy and a reduced quality of life. ObjectiveTo determine the proportion of children who reintroduced peanut or tree nuts after a negative OFC and to describe factors that influenced decisions regarding reintroduction or avoidance of nonallergic (negative) nuts. MethodsFamilies of children that had undergone an OFC for peanut or tree nuts at Sydney Children's Hospital were invited to participate. Consenting families were sent an online questionnaire. ResultsThe response rate to the questionnaire was 64%. More than 85% of respondents had introduced all or some of the negative nuts after the OFC and most had maintained at least some regular exposure in the child's diet at the time of the study. The age at diagnosis of the nut allergy and an awareness of the benefit of introducing foods after a negative OFC were significantly (P < .05) associated with introducing negative nuts. There was improved quality of life in those that introduced negative nuts. ConclusionMost families introduced or attempted to introduce negative nuts after a negative OFC. Educating families on the benefits of introducing foods after a negative OFC result is an important factor contributing to successful reintroduction.

Evaluating otter reintroduction outcomes using genetic spatial capture-recapture modified for dendritic networks.

Monitoring the demographics and genetics of reintroduced populations is critical to evaluating reintroduction success, but species ecology and the landscapes that they inhabit often present challenges for accurate assessments. If suitable habitats are restricted to hierarchical dendritic networks, such as river systems, animal movements are typically constrained and may violate assumptions of methods commonly used to estimate demographic parameters. Using genetic detection data collected via fecal sampling at latrines, we demonstrate applicability of the spatial capture–recapture (SCR) network distance function for estimating the size and density of a recently reintroduced North American river otter (Lontra canadensis) population in the Upper Rio Grande River dendritic network in the southwestern United States, and we also evaluated the genetic outcomes of using a small founder group (n = 33 otters) for reintroduction. Estimated population density was 0.23–0.28 otter/km, or 1 otter/3.57–4.35 km, with weak evidence of density increasing with northerly latitude (β = 0.33). Estimated population size was 83–104 total otters in 359 km of riverine dendritic network, which corresponded to average annual exponential population growth of 1.12–1.15/year since reintroduction. Growth was ≥40% lower than most reintroduced river otter populations and strong evidence of a founder effect existed 8–10 years post‐reintroduction, including 13–21% genetic diversity loss, 84%–87% genetic effective population size decline, and rapid divergence from the source population (F ST accumulation = 0.06/generation). Consequently, genetic restoration via translocation of additional otters from other populations may be necessary to mitigate deleterious genetic effects in this small, isolated population. Combined with non‐invasive genetic sampling, the SCR network distance approach is likely widely applicable to demogenetic assessments of both reintroduced and established populations of multiple mustelid species that inhabit aquatic dendritic networks, many of which are regionally or globally imperiled and may warrant reintroduction or augmentation efforts.

Impact of climate change on the success of population support management and plant reintroduction at steep, exposed limestone outcrops in the German Swabian Jura

Species-rich rocky outcrops and cliff vegetation in central Europe distributed outside alpine regions are typically associated with historical landscapes of interrelated natural and cultural features such as the Swabian Alb in Germany. Consequently, in these regions, biodiversity is highly threatened by various factors, such as land use change and increased land use intensity. In central Europe, the flagship species closely associated with these vegetation types is Cheddar Pink (Dianthus gratianopolitanus), whose total European population is declining. Herein, we exemplified a successful reintroduction experiment at two different sites at the species’ distribution center in Germany on the Swabian Alb. In total 549 individuals were reintroduced in 2017 and 2018 and monitored in the field until 2020. Using a subset of clonally replicated plants it was shown under controlled conditions in greenhouses during 2016–2019 that climate change and, in particular, increased temperature sum in late winter and during spring had a great effect on the phenology and population fitness of D. gratianopolitanus ex situ. It was demonstrated that these effects were independent of genetic variation and cultivation effects. Global climate change and increased temperature sums not only caused significant earlier flowering, but also significantly reduced number of flowers and seed set, thereby drastically affecting population viability in a negative way. We concluded that ecological micro-niches of the studied species are spatially shifting and that the germination and seedling phases will become increasingly crucial for its long-term population persistence. Our study has potential implications for future cliff management and successful long-term habitat protection strategies.

Effective number of breeders and reconstructed sibships reveal low reproductive output by a reintroduced population of endangered fish

Abstract Fishes with periodic life histories are long‐lived, slow to mature, and have intermittent periods of successful recruitment, limiting the ability of managers to recover their populations rapidly. Endangered razorback sucker (Xyrauchen texanus) in the Colorado River Basin, USA, is a periodic strategist whose persistence is largely dependent on hatchery augmentation. Stocking efforts have increased population sizes in the basin; however, natural recruitment remains extremely limited. Annual reproductive output of a reintroduced population of razorback sucker was evaluated over a 10‐year period in a Colorado River tributary by estimating the effective number of breeders (Nb) and numbers of repeat spawning adults through genetic analysis of wild‐spawned larval cohorts. Comparative estimates were also obtained for a self‐sustaining sympatric periodic strategist, flannelmouth sucker (Catostomus latipinnis). Given known trade‐offs between delayed maturation and long lifespan, population size and age‐structure of razorback sucker was quantified to assess potential demographic constraints to reproductive output. The results showed consistently low annual Nb estimates for razorback sucker ( = 127), compared with flannelmouth sucker ( = 3,022) and within the same period (2013–2018) an order of magnitude more repeat spawning individual razorback sucker (n = 41) were detected compared with flannelmouth sucker (n = 4). Given the relatively young age structure of the razorback sucker population (median = age 4), the results indicate that successful recruitment may be limited by the number of spawning adults. These results highlight the importance of understanding how life history characteristics may affect the rate and success of reintroductions and where life‐stage specific bottlenecks to reproduction and recruitment may occur. Given the increasing necessity of stocking for most reintroductions, management of periodic strategists may need to aim at increasing the relative age‐structure of adults to bolster reproductive output in addition to increasing juvenile survival.

Linking the past and present to predict the distribution of Asian crested ibis (Nipponia nippon) under global changes

Understanding how species' ecological niches adapt to environmental changes through time is critical for predicting the effect of future global change on endangered species. Yet few studies have incorporated knowledge of past niche shifting into the assessment of species' future fate in a changing world. In this study, we integrated the ecological niche dynamics into the species distribution modeling of the Asian crested ibis (Nipponia nippon) in East Asia. Specifically, we compared historical and present ecological niches of crested ibis in four-dimensional environmental space based on species occurrence and environmental data. We then employed a multi-temporal ecological niche model to estimate the potential geographical distribution of crested ibis under future climate and land-use changes. Our results show that crested ibis retained similar though not identical ecological niches over time. Compared to the historical baseline range, the current suitable habitat for crested ibis has been reduced by 39.6%. The effects of human activity outweigh those of climate change regarding the distribution of crested ibis. We conclude that the ecological niche of crested ibis was tended to be conservative, and future potentially suitable habitat may encounter northeastward and northwestward shift, and possibly expand by 18.7% referred to the historical range. The findings of our study are of clear importance for the conservation and successful reintroduction of crested ibis in East Asia.

Factors influencing establishment success in reintroduced black-faced spider monkeys Ateles chamek.

Establishing reintroduced primates in a suitable predetermined area has proven to be a challenge. Establishment is the first major step that has to be taken in the long process of reintroduction. When this first goal is not achieved, the chances of success decline drastically. Understanding the main determinants of establishment is therefore crucial for reintroduction success. This study examined the influence of three independent factors on the establishment success of reintroduced spider monkeys. We analysed data from the releases of eight groups of black-faced spider monkeys (Ateles chamek), which are part of the official reintroduction program of spider monkeys in the South Eastern Peruvian Amazon. Establishment success was measured by the proportion of individuals within groups that were found in the target area 6 months after release. The hours research assistants and volunteers spent with the group within the first 3 months after release-in the context of post-release monitoring-was shown to have a positive effect on the establishment success of the released group in the target area. The presence of an already established group in the area was also found to have a significant positive effect on establishment success. The influence of the days of post-release food provisioning had no effect. Our findings emphasize the importance of long-term monitoring programs to help increase the efficiency of primate reintroductions.

Genetic Differentiation of Reintroduced Père David's Deer (Elaphurus davidianus) Based on Population Genomics Analysis.

The reintroduction is an important conservation tool to restore a species in its historically distribution area, but the rate of reintroduction success varies across species or regions due to different reasons. Genetic evaluation is important to the conservation management of reintroduced species. Conservation concerns relate to genetic threats for species with a small population size or severely historically bottle-necked species, such as negative consequences associated with loss of genetic diversity and inbreeding. The last 40years have seen a rapid increasing of population size for Père David’s deer (Elaphurus davidianus), which originated from a limited founder population. However, the genetic structure of reintroduced Père David’s deer has not been investigated in terms of population genomics, and it is still not clear about the evolutionary history of Père David’s deer and to what extent the inbreeding level is. Conservation genomics methods were used to reconstruct the demographic history of Père David’s deer, evaluate genetic diversity, and characterize genetic structure among 18 individuals from the captive, free-ranging and wild populations. The results showed that 1,456,457 single nucleotide polymorphisms (SNPs) were obtained for Père David’s deer, and low levels of genome-wide genetic diversity were observed in Père David’s deer compared with Red deer (Cervus elaphus) and Sika deer (Cervus nippon). A moderate population genetic differentiation was detected among three populations of Père David’s deer, especially between the captive population in Beijing Père David’s deer park and the free-ranging population in Jiangsu Dafeng National Nature Reserve. The effective population size of Père David’s deer started to decline ~25.8ka, and the similar levels of three populations’ LD reflected the genetic impacts of long-term population bottlenecks in the Père David’s deer. The findings of this study could highlight the necessity of individual exchange between different facilities, and genetic management should generally be integrated into conservation planning with other management considerations.

Precocious Maturation in Spring‐Run Chinook Salmon Is Affected by Incubation Temperature, Feeding Regime, and Parentage

AbstractSalmonid populations of the Central Valley of California have been in decline for decades, making hatchery practices that combine conservation strategies with targeted research essential to optimize recruitment to adulthood. Hatchery populations generally exhibit a higher incidence of precocious male maturation than natural populations. However, optimal hatchery management practices pertaining to incubation, feeding, and genetic predisposition have yet to be optimized to lower the incidence of precocity in hatchery‐reared male spring‐run Chinook Salmon Oncorhynchus tshawytscha. To further assess this, we conducted a 2 × 2 factorial experiment exploring the effect of embryo incubation temperature (cold or warm) and post‐ponding ration (high or low) on incidence of age‐1 precocious male maturation. Fertilized eggs from each parental cross were placed among each treatment group to control for genetic variation and track any genetic predisposition. Precocity rate at year 1 was affected by incubation temperature and feed rate. There were also significant differences in growth rate and body condition among the treatment groups during early development. Additionally, the precocious males were nonrandomly produced by the crosses, suggesting a significant parentage effect on precocity. Optimization of Chinook Salmon rearing techniques is critical—not only to lessen the incidence of precocity and identify the causal parameters, but also to maximize successful reintroduction.

Movement Dynamics and Survival of Stocked Colorado River Cutthroat Trout

AbstractThe ability of native fish to establish self‐sustaining populations when reintroduced to vacant habitats is variable. We evaluated factors that potentially affect the reintroduction success of juvenile Colorado River Cutthroat Trout Oncorhynchus clarkii pleuriticus that were reintroduced to an isolated watershed and were experiencing suboptimal survival and recruitment. We conducted a 3‐year mark–recapture study to model annual apparent survival probability as it related to (1) different ex situ rearing strategies and (2) initial release among different habitat types. The use of PIT tags also enabled the quantification of loss via emigration. Apparent survival was highest for small fish that were minimally exposed to ex situ rearing conditions, stocked in small, headwater stream reaches. However, maximum estimates of apparent survival remained low (≤0.38 ± 0.05 [estimate ± SE]) regardless of rearing treatment, stocking location, or interactive effects between covariates. Emigration of stocked fish (&lt;1%) from the study area did not appear to limit their establishment. Our results suggest that variation in stocking and rearing strategy may have some effect on translocation success and the interaction between rearing and stocking strategy highlights the importance of considering the life history stage of stocked individuals when identifying stocking sites. Consistently low annual survival values may be indicative of a larger issue, requiring in‐depth evaluation of adaptive potential within our brood source and other factors that potentially limit population persistence.

Iberian Lynx (Lynx pardinus) personality: A rating assessment with ex Situ Conservation Program sample.

Research on felid personality has been conducted in a few species. Further research on new species could be highly informative in regard to the influence that adaptation to different ecological challenges has on felid personality. We evaluated the personality of 58 Iberian lynxes (Lynx pardinus) hosted at 3 different breeding centers for reintroduction. A total of 43 adjectives obtained from previous studies with felids were assessed by 30 raters according to the knowledge on the lynx behavior they acquired by observing a live video feed of the animals, finding acceptable standards of interrater reliability. Principal components analysis and regularized exploratory factor analysis revealed 4 factors. Based on the pattern of factor loadings and on previous labeling in felid personality research, we labeled the factors as Boldness, Dominance, Neuroticism, and Attentiveness. The results were similar to that of the previous studies on felids, although some differences were found, which could be due to the evolutionary distance among species and to methodological differences among studies. Future research on endangered felids could provide insights into the influence of personality on conservation outcomes related to successful breeding and reintroduction. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Raptor reintroductions: Cost‐effective alternatives to captive breeding

AbstractReintroductions are becoming a popular tool to prevent extinctions, although their overall success rate is low. Assessing the efficiency and cost‐effectiveness of different reintroduction strategies may help identify and promote efficient practices. Captive‐breeding is widely used in animal reintroductions, although concerns have been raised about relatively high failure rates and economic costs. Here, we compared the effectiveness of two simultaneously used strategies in the reintroduction of the Bonelli’s eagle on the island of Mallorca: The release of captive‐bred chicks and wild‐reared, translocated non‐juveniles. To do so, we estimated the main vital rates for individuals released by both strategies and used these to perform population simulations to assess their overall performances. The use of wild‐reared non‐juveniles showed a trend with higher numbers of breeding pairs 10 years after the end of releases (14.75 pairs, 95% CI 4–25 vs. 11.21 pairs, 95% CI 2–24) and was the only strategy that prevented extinction in the long term. Following that, based on cost estimations of every strategy and different reintroduction budgets, we assessed the cost‐effectiveness of releasing wild‐reared non‐juveniles compared with two captive‐breeding alternatives: Releasing chicks either originally from breeding programmes or extracted from nests in natural populations. Again, releasing wild‐reared non‐juveniles was the only strategy that prevented long‐term extinction in all economic scenarios (i.e. low‐budget scenario 21.49 pairs, 95% CI 2–25). The use of chicks sourced from captive‐breeding programmes did not guarantee long‐term persistence even in high‐budget scenarios (14.50 pairs, 95% CI 0–25). Releasing wild‐reared non‐juveniles boosts early recruitment to the breeding population and early reproduction, which can be key for reintroduction success. However, in some scenarios, post‐release effects can be stronger in wild‐reared individuals, especially because of high translocation stress and post‐release dispersal. Hence, we recommend undertaking careful evaluation of the pros and cons of every strategy and embracing adaptive management to choose best strategies.

One of these wolves is not like the other: morphological effects and conservation implications of captivity in Mexican wolves

AbstractMaintaining animal populations in captivity can be a useful way to conserve species, especially those that are extinct in the wild or endangered in their native habitats. These animals could be reintroduced into the wild from captivity if conditions improve. However, captive populations of endangered species are often established with few wild‐caught individuals and are maintained in novel habitats, conditions which may make these populations prone to morphological divergence. Changes in cranial morphology, in particular, may limit reintroduction success because these morphological changes may alter cranial functionality related to capturing and consuming prey. To assess whether unintentional morphological changes occur in captivity, we examined the crania and mandibles of 275 specimens of wild, captive and reintroduced Mexican wolvesCanis lupus baileyi. We detected significant differences in skull size and shape among these populations. Captive specimens displayed the greatest overall shape variation and were significantly differentiated from the wild population in regions of the skull that are essential to cranial functionality. The reintroduced population displayed the narrowest trait distribution, with cranial morphology that grouped consistently with the captive morphotype. The small number of individuals of the founding population along with the increased variation in cranial morphology among captive Mexican wolves suggests that morphological changes in captivity may be related to genetic changes such as genetic drift or relaxed selection. This study helps to define the changes that may occur in captivity, the potential mechanisms behind these shifts, and the ways in which morphological variation in captive populations may impact conservation initiatives.

Natural Recruitment Potential of a Reintroduced Shovelnose Sturgeon Population in the Bighorn River, Wyoming

AbstractShovelnose Sturgeon Scaphirhynchus platorynchus were extirpated from the Bighorn River, Wyoming during the 20th century after the construction of two main‐stem dams and the resulting modifications to fish passage and flow and thermal regimes. The species was reintroduced to the river between 1996 and 2020, but nothing was known about how these fish used the river and whether they could sustain themselves without consistent stocking. Radio telemetry during 2015–2018 identified at least two putative spawning locations 95.6 and 139.5 river kilometers upstream from a reservoir transition zone. Temperature and velocity data suggest that most of the drifting larvae will have insufficient fluvial habitat to complete their drift stage and are likely to enter the Bighorn Lake transition zone. Benthic dissolved oxygen concentrations in the reservoir transition zone were low enough to cause recruitment reduction or failure for drifting larvae that reach this habitat. Future monitoring will determine whether this population persists, but this study highlights the importance of understanding species life history and the causes of extirpations to better predict reintroduction success.

Quest for New Space for Restricted Range Mammals: The Case of the Endangered Walia Ibex

Populations of large mammals have declined at alarming rates, especially in areas with intensified land use where species can only persist in small habitat fragments. To support conservation planning, we developed habitat suitability models for the Walia ibex (Capra walie), an endangered wild goat endemic to the Simen Mountains, Ethiopia. We calibrated several models that differ in statistical properties to estimate the spatial extent of suitable habitats of the Walia ibex in the Simen Mountains, as well as in other parts of the Ethiopian highlands to assess potentially suitable areas outside the current distribution range of the species. We further addressed the potential consequences of future climate change using a climate model with four emission scenarios. Model projections estimated the potential suitable habitat under current climate to 501–672 km2 in Simen and 6,251–7,732 km2 in other Ethiopian mountains. Under projected climate change by 2,080, the suitable habitat became larger in Simen but smaller in other parts of Ethiopia. The projected expansion in Simen is contrary to the general expectation of shrinking suitable habitats for high-elevation species under climate warming and may partly be due to the ruggedness of these particular mountains. The Walia ibex has a wide altitudinal range and is able to exploit very steep slopes, allowing it to track the expected vegetation shift to higher altitudes. However, this potential positive impact may not last long under continued climate warming, as the species will not have much more new space left to colonize. Our study indicates that the current distribution range can be substantially increased by reintroducing and/or translocating the species to other areas with suitable habitat. Indeed, to increase the viability and prospects for survival of this flagship species, we strongly recommend human-assisted reintroduction to other Ethiopian mountains. Emulating the successful reintroduction of the Alpine ibex that has spread from a single mountain in Italy to its historical ranges of the Alps in Europe might contribute to saving the Walia ibex from extinction.

Translocation, survival, and recovery of Kansas‐banded Canada geese

AbstractTemperate‐breeding, or resident, Canada geese were once extirpated in Kansas, USA, but currently provide abundant viewing and hunting opportunities. Kansas Department of Wildlife, Parks, and Tourism (KDWPT) began reintroducing geese in 1980 with a goal of re‐establishing a breeding population. Successful reintroductions led to translocating flocks to regions with no previous records of nesting geese; however, KDWPT continues to translocate individuals from nuisance flocks in urban areas to rural reservoirs to reduce human conflicts with urban geese. Our goal was to determine the effects of such translocations on survival and recovery of adult, sub‐adult, and juvenile temperate‐breeding Canada geese. We used Brownie dead‐recovery models in Program MARK to compare survival and recovery probabilities between translocated and nontranslocated (normal wild) Kansas‐banded Canada geese for 2012–2017. Model‐estimated annual survival differed between status (normal wild = 0.761, 95% CI 0.734–0.785; translocated = 0.598, 95% CI 0.528–0.665). Recovery probability differed between normal and translocated adults (normal wild = 0.074, 95% CI = 0.069–0.078; translocated = 0.138, 95% CI = 0.120–0.158) and juveniles (normal wild = 0.067, 95% CI = 0.059–0.075; translocated = 0.250, 95% CI = 0.199–0.310). Recovery probability did not differ between status in the sub‐adult age class (normal wild = 0.126, 95% CI = 0.115–0.137; translocated = 0.090, 95% CI = 0.055–0.144). Translocation is a viable management option to successfully reduce survival and increase recovery probability of urban nuisance geese in Kansas.

Reintroduction of Bilbies (Macrotis lagotis) to Matuwa, an Indigenous Protected Area in Western Australia

The greater bilby (Macrotis lagotis) once occupied much of Australia's mainland. Bilbies are now listed as vulnerable and only occur in 20% of their former range. Operation Rangeland Restoration aims to to restore an ex−pastoral lease; reintroduce several species of locally extirpated fauna, including the bilby; and maintain the area in perpetuity for the conservation of Australian arid zone species. Bilbies were reintroduced to the Matuwa Indigenous Protected Area between 2007 and 2010 and, with ongoing landscape-scale control of feral predators, herbivores, and fire, have thrived. Here, we present a detailed account of the methods used during the reintroduction, showing that between 2007 and 2019 there has been an 88% increase in the area of occupancy by bilbies at Matuwa. The results of 2-ha track plot surveys conducted by the traditional owners of Matuwa suggest that the reintroduced bilbies are emigrating out of Matuwa. In addition, in 2018 and 2019 we used 120 camera-traps over 18 mo and occupancy analysis to confirm the widespread presence of bilbies across Matuwa and define significant habitat correlates. Bilbies were more likely to be detected on sandplains with Eucalyptus species as overstorey vegetation and Triodia as understorey vegetation. Bilbies were not detected in habitats with ≥ 75% bare ground. We attribute the success of the bilby reintroduction at Matuwa to the consistent implementation of landscape-scale control of feral predators.

Fundamental dietary specialisation explains differential use of resources within a koala population.

The diets of individual animals within populations can differ, but few studies determine whether this is due to fundamental differences in preferences or capacities to eat specific foods, or to external influences such as dominance hierarchies or spatial variation in food availability. The distinction is important because different drivers of dietary specialisation are likely to have different impacts on the way in which animal populations respond to, for example, habitat modification. We used a captive feeding study to investigate the mechanisms driving individual dietary specialisation in a population of wild koalas (Phascolarctos cinereus) in which individuals predominantly ate either Eucalyptus viminalis or Eucalyptus obliqua foliage. All six koalas that primarily ate E. viminalis in the wild avoided eating E. obliqua for more than 1 month in captivity. In contrast, all seven koalas that primarily ate E. obliqua could be maintained exclusively on this species in captivity, although they ate less from individual trees with higher foliar concentrations of unsubstituted B-ring flavanones (UBFs). Our results show that fundamental differences between individual animals allow some to exploit food resources that are less suitable for others. This could reduce competition for food, increase habitat carrying capacity, and is also likely to buffer the population against extinction in the face of habitat modification. The occurrence of fundamental individual specialisation within animal populations could also affect the perceived conservation value of different habitats, translocation or reintroduction success, and population dynamics. It should therefore be further investigated in other mammalian herbivore species.